The production of high efficiency Ziegler–Natta catalyst with dual active sites nature using cyclohexyl chloride as promoter with super activity and produced superior polyethylene with controllable molecular weight distribution

Figures & data

Table 1. The effect of Al/Ti ratio on the optimum HC/Ti, catalyst yield and polymer molecular specification.

Al/Ti	HC/Ti	Catalyst yield		H2/C2H4 = 2/6.5
		H2/C2H4 = 0/8.5	H2/C2H4 = 2/6.5	MFI5	MFI21	FRR	Increase in hydrogen responsibility ratio (%)	Mw*10^−5 (g/mol)	MWD	Wax (%)
40	15	27.4	18.23	0.62	5.2	8.4	55	1.8	3.6	0.71
	0	12.3	9.55	0.40	4.1	10.3		2.2	4.2	0.78
80	50	31.2	27.25	0.64	5.7	8.9	52	1.6	3.7	0.75
	0	15.4	13.12	0.42	4.3	10.2		2.1	4.1	0.82
120	95	35.6	32.47	0.68	6.4	9.4	51	1.5	3.8	0.77
	0	19.9	16.29	0.45	4.7	10.4		1.9	4.4	0.85
160	115	38.4	34.72	0.72	7.6	10.6	44	1.3	4.5	0.76
	0	21.4	18.64	0.50	5.7	11.4		1.6	4.6	0.86

Note: P: 8.5 bar, T: 83 °C, t: 1 h, Stirrer rate: 500 rpm.

Figure 1. Effect of cyclohexyl chloride on the Rp (catalyst activity) during the polymerization time; HC/Ti: 0 and 95 (without organocatalyst and with organocatalyst respectively), P: 8.5 bar, T: 83 °C, Al/Ti: 120, t: 1 h, Stirrer rate: 500 rpm.

Table 2. The effect of Al/Ti and optimum HC/Ti ratios on the polymer powder.

Al/Ti	HC/Ti	APS (micron)	d0.1 (micron)	d0.5 (micron)	d0.9 (micron)	PSD span	Bulk density (g/cm^3)
40	15	197	73.9	150.3	389.2	2.10	0.41
	0	135	64.1	111.3	215.4	1.36	0.37
80	50	206	75.6	163.7	400.4	1.98	0.41
	0	141	66.2	113.8	229.8	1.44	0.38
120	95	211	76.5	169.4	403.2	1.93	0.41
	0	154	67.4	117.6	245.1	1.51	0.39
160	115	227	78.0	187.7	428.4	1.87	0.42
	0	158	69.3	121.8	265.9	1.61	0.39

Note: P: 8.5 bar, T: 83 °C, t: 1 h, Stirrer rate: 500 rpm.

Figure 2. The effect of Al/Ti and optimum HC/Ti ratios on the cumulative PSD of produced PE’s P: 8.5 bar, T: 83 °C, t: 1 h, Stirrer rate: 500 rpm.

Table 3. The effect of cyclohexyl chloride injection on the catalyst specification.

Properties value	0	50	100	200	500
Surface area (m^2/g)	110.8	123.5	117.9	121.4	114.3
Pore volume (mL/g)	0.17	0.18	0.17	0.19	0.18
Average pore radius (Å)	17.3	15.5	16.1	16.5	15.9
APS (μm)	10.7	11.2	11.3	11.1	11.5
Ti (%)	3.8	4.2	4.3	4.1	4.5
Mg (%)	19.5	19.1	18.9	18.8	19.0
Cl (%)	56.2	56.3	55.9	56.5	55.8

Table 4. The effect of cyclohexyl chloride injection during the catalyst preparation on the catalyst yield and polymer molecular specification.

HC/Ti (ppm)	Catalyst yield		H2/C2H4 = 2/6.5
	H2/C2H4 = 0/8.5	H2/C2H4 = 2/6.5	MFI5	MFI21	FRR	Mw*10^−5 (g/mol)	MWD	Wax (%)
0	19.9	16.3	0.45	4.72	10.5	1.9	4.4	0.85
50	22.3	19.8	0.49	7.74	15.8	1.7	6.7	0.83
100	24.4	21.2	0.53	10.10	19.1	1.6	8.1	0.83
200	25.2	21.9	0.58	11.80	20.3	1.4	8.3	0.81
500	29.6	25.4	0.72	13.40	18.6	1.2	8.1	0.79

Note: P: 8.5 bar, T: 83 °C, Al/Ti: 120, t: 1 h, Stirrer rate: 500 rpm.

Figure 3. The effect of cyclohexyl chloride injection during the catalyst preparation on the molecular weight distribution of produced PE’s P: 8.5 bar, T: 83 °C, catalyst: 1 mg, Al/Ti: 120, t: 1 h, Stirrer rate: 500 rpm.

Table 5. The effect of cyclohexyl chloride injection during the catalyst preparation on the polymer powder.

HC/Ti (ppm)	APS	d10 (micron)	d50 (micron)	d90 (micron)	PSD span	Bulk density (g/cm^3)
0	154	67.3	117.6	242.1	1.49	0.39
50	159	67.6	122.1	253.7	1.52	0.40
100	163	69.3	124.6	260.3	1.53	0.41
200	172	70.2	127.2	282.5	1.67	0.42
500	181	72.7	131.5	306.8	1.78	0.42

Note: P: 8.5 bar, T: 83 °C, Al/Ti: 120, t: 1 h, Stirrer rate: 500 rpm.

Figure 4. The effect of cyclohexyl chloride injection during the catalyst preparation on the cumulative PSD of produced PE’s P: 8.5 bar, T: 83 °C, catalyst: 1 mg, Al/Ti: 120, t: 1 h, Stirrer rate: 500 rpm.